What is subchondral sclerosis of the knee joint and how is it treated?

Subchondral sclerosis of joint surfaces is a degenerative-dystrophic disease of the joints, which is characterized by primary degeneration of articular cartilage with subsequent changes in the articular surfaces and the development of marginal osteophytes. This subsequently leads to joint deformation.

Degenerative diseases cannot be cured. Etiotropic treatment is aimed at slowing down the progression of the disease and not leading to endoprosthetics.

The efforts of neurologists at the Yusupov Hospital are aimed at stabilizing the patient’s condition, achieving stable remission and preventing disability. Timely contact with doctors will improve the patient’s condition and quality of life.

Osteoarthritis of the knee joint. Causes

Osteoarthritis of the knee joint is a chronic disease in which degenerative-dystrophic changes in cartilage lead to complete destruction of the intra-articular lining. Clinical symptoms are pain, limited joint mobility.

More often, gonarthrosis is diagnosed in women 45+, professional athletes, overweight people engaged in heavy, monotonous physical labor.

It is impossible to name a single reason leading to the development of the disease. A number of unfavorable factors weaken cartilage. The onset of the disease is a fatal coincidence of circumstances.

Contribute to the occurrence of the disease:

• knee injuries (fractures, dislocations, meniscal injuries), surgical interventions on joints;
• aging (with age, cartilage loses its elasticity and cracks easily);
• systemic autoimmune diseases (rheumatism, rheumatoid arthritis, lupus erythematosus, etc.);
• endocrine pathologies (diabetes mellitus, hypothyroidism), menopause;
• genetic factors (vulnerable cartilage tissue, insufficiency of synovial fluid);
• excess weight (excessive load on joints);
• hypothermia and dehydration;
• overload of the knee joints during heavy work and sports;
• pathology of the hip joints.

Low physical activity also contributes to the development of arthrosis. With a sedentary lifestyle, the blood supply to the lower extremities decreases, metabolic processes slow down, muscles, ligaments, tendons atrophy, and cartilaginous structures degenerate.

Definition of the concept

If we specify what sclerosis of articular surfaces is, then it is more appropriate to talk about local death of living tissue cells in the area of ​​​​the bone connection.

The smooth surfaces of the bone zones are covered with articular cartilage, which is involved in the formation of a movable joint. Below it is a subchondral plate, tightly fused to the bone. A thin layer provides cartilage, which does not have its own blood circulation and innervation, with all the necessary nutrients. Mutually beneficial “cooperation” continues as long as the cartilage tissues have sufficient hydrophilicity and shock absorption ability.

If cartilage loses its properties, the entire load falls on the subchondral plate. Gradual compression destruction of functional tissues begins. Subsequently, the dead cells are replaced by fibrous fibers. The structural element of the bone tissue thickens, the vessels feeding the cartilage become clogged, and the process of ossification begins.

The surface of the damaged bone becomes a springboard for the formation of bone growths. The number and size of exostoses and osteophytes increases methodically. In proportion to the growth of tumors, the range of movements is limited.

Symptoms of osteoarthritis of the knee joint

The course of the disease is variable and depends on the age and physical condition of the patient, the cause of the pathology, and concomitant diseases. As a rule, pain in the knees during exercise, swelling, burning in the affected joint, numbness after prolonged immobility, dry crunching, clicking when moving are a concern.

The diagnosis of the disease is made by an orthopedic doctor after examination, questioning and additional examinations.

Osteoarthritis of the knee joint 1st degree

The disease is often asymptomatic. Sometimes patients experience slight discomfort, tension, and warmth in the knee joint.

A typical clinical picture of first degree gonarthrosis includes:

• pain during movement or at rest after significant loads, at the moment of maximum flexion and extension;
• burning, swelling and hyperemia of the knee after exercise (symptoms of inflammation);
• X-ray examination reveals single osteophytes and narrowing of the joint space.

Important!
Clinical symptoms typical of the first stage of the disease may be accompanied by significant destruction of cartilage. Timely diagnosis is important, since conservative treatment is more effective at the initial stage of the disease.

Osteoarthritis of the knee joint grade 2

The pain becomes more intense and prolonged, the functionality of the joint is limited (the amplitude of voluntary movements decreases). The knee joint begins to deform due to uneven wear of the cartilage (“flattened”), and pathological bending of the lower limb is possible. Typical signs of grade 2 osteoarthritis:

• constant pain during exercise, more pronounced in the morning and evening;
• persistent discomfort in the joint even after a long rest;
• decreased range of motion;
• increase in joint volume, atrophy of periarticular soft tissues;
• crunching noise during sudden movements, squats, and sometimes when walking.

X-ray examination reveals osteophytes, narrowing of the joint space is possible up to 30-40%. As a rule, medical help is sought precisely at this stage, when the quality of life is significantly reduced.

Osteoarthritis of the knee joint 3rd degree = deforming osteoarthritis of the knee joint

At the final stage, the disease disables the patient, since the cartilage tissue is almost completely destroyed, the joint space is narrowed to the maximum, and sometimes absent. Multiple osteophytes and deformation of articular segments of bones are determined. It is possible to block the joint due to a fragment of osteophyte getting into the joint space. The leg is not functional and constantly bothers me. Movement is often only possible with the help of a cane, crutches, or walker.

The following symptoms are typical:

• constant pain in the joint;
• severe deformation of the joint;
• immobility of the knee joint;
• lameness when walking, there may be shortening of the limb;
• swelling of the joint due to excessive accumulation of intra-articular fluid;
• numbness of the leg, decreased sensitivity;
• significant atrophy of the musculo-ligamentous apparatus of the joint.

Osteoarthritis affects joint bone tissue, increasing the risk of fractures. At this stage, only surgical treatment is effective. Conservative methods help reduce pain, slightly increase range of motion, and temporarily improve quality of life.

Therapeutic methods

Since subchondral sclerosis of the spine is rarely a self-occurring disease, it should be treated primarily as a symptom and complication of the underlying disease. The point of therapy is to relieve the patient of pain and improve overall well-being. All treatment is divided into two stages.

Table. Stages of therapy

Signs of osteoarthritis of the knee joint

The main clinical symptoms of the disease: knee pain, limited mobility, joint deformity, aseptic inflammation of the synovium (synovitis).

Knee pain

Pain in the joint can vary from severe, limiting joint mobility, to barely noticeable with certain movements. In the initial stages of OAC, the pain is insignificant and occurs with prolonged sitting in an uncomfortable position, long walking, or lifting heavy objects. They go away quickly after rest and get worse in cold and damp weather.

The cause of severe pain in the knee is reactive inflammation of the joint (synovitis) or periarticular soft tissues (muscles, tendons, bursae). When periarticular soft tissues are involved in the inflammatory process, the pain intensifies with certain movements, and “starting” pain is characteristic (pain and stiffness after a period of rest).

Limitation of joint mobility

Due to the destruction of cartilage, the proliferation of osteophytes, and a deficiency of synovial fluid, the biomechanics of the joint is disrupted, which leads to a limited range of movements up to complete immobility in the last stage.

Knee deformity

Due to the uneven destruction of cartilage and subchondral bone tissue, the joint loses its usual shape (deforms). The muscles, tendons, and ligaments that form the joint atrophy.

Synovitis

Synovitis is a reactive inflammation of the inner lining of the joint. Aseptic (microbial-free) inflammation inside the joint occurs due to irritation and damage to the synovial membrane with pieces of destroyed cartilage. The inflammatory pain is intense, intensifies with movement, the knee increases in volume. The process subsides on its own, but can resume under unfavorable conditions.

Pathogenesis of arthrosis of the knee joints

Morphologically, arthrosis is wear and tear of the cartilage lining of the joint, leading to disruption of the normal anatomical structure of the articular surfaces. The joint is formed by the articular surfaces of the tibia and femur, covered with cartilage tissue. During movements, cartilage acts as a shock absorber. Cartilage consists of connective tissue fibers loosely located in a jelly-like substance (matrix). Due to the matrix, cartilage is nourished and regenerated.

Cartilage tissue is like a sponge: at rest it absorbs fluid, and when loaded, squeezes it into the joint cavity, allowing the bones to glide. Under load, some of the fibers are worn out and destroyed. Normally, they are replaced by newly synthesized ones. Osteoarthritis occurs when there is an imbalance between the synthesis of cartilage and its destruction.

Damaged, less complete cartilage structure absorbs less fluid, drier and more brittle cartilage easily splits under stress. The structure of the underlying bone changes - osteophytes grow along the edges of the joint, compensating for the loss of cartilage by the growth of articular surfaces.

Not only the cartilaginous covering of the joint suffers; meniscal tears, cruciate ligament injuries are periodically diagnosed with DOA, and sometimes loose intra-articular bodies are detected. Due to partial or complete destruction of the cartilage and subchondral plate, the contact surfaces are displaced, causing the joint to become deformed.

Deforming osteoarthritis of the knee joint is arthrosis of the last stage.

Primary arthrosis of the knee joint

Primary ACS is considered if the immediate causes of the disease have not been identified (there were no injuries, no concomitant diseases, no professional history).

Secondary arthrosis of the knee joint

Secondary AKS is degenerative-dystrophic changes in the knee joint due to metabolic diseases (diabetes mellitus, gout), rheumatoid diseases (rheumatoid arthritis), vascular pathology (vasculitis, atherosclerosis) or in the presence of a professional history (sports, heavy physical labor) .

What is subchondral osteosclerosis

Subchondral osteosclerosis is characterized by hardening of the bones under the lower surface of the cartilage, as well as a disruption of its blood supply and structure.

Joint sclerosis is particularly dangerous because it threatens with limitation of motor activity and early disability. A thinned bone, while remaining dense, breaks both with minor injuries and under the weight of its body.

Diagnostics

To verify the diagnosis, special examination methods are prescribed. The most informative are: X-ray, magnetic resonance imaging and arthroscopy. X-rays reveal narrowing of the joint space and deformation of the articular surfaces. The degree of damage to cartilage, menisci, and ligaments can be assessed using an MRI examination.

Diagnostic arthroscopy is an examination of articular cartilage using endoscopic equipment. Softening and degeneration of the articular lining (chondromalacia) of varying severity are detected.

1st degree. Superficial damage to articular cartilage. The cover is uneven, degeneratively changed.

2nd degree. Deep destruction - fiber disintegration, cracking.

3rd degree. Profound changes, pronounced thinning of cartilage.

4th degree. Through defects of cartilage with exposure of underlying bones.

Classification of ACS

According to the Kosinski classification of ACS, three stages of the disease are distinguished according to radiological and clinical manifestations. They focus on the degree of narrowing and unevenness of the joint space, deformation of the articular surfaces, changes in the subchondral bone (osteosclerosis).

First stage of gonarthrosis

The changes are almost invisible. The joint space is normal or slightly narrowed, with isolated tiny osteophytes at the edge of the articular surfaces.

Clinically - mild short-term pain after significant fatigue, minimal impairment of knee function. Most do not perceive these symptoms as a pathology and do not seek medical help.

Second stage of gonarthrosis

The joint space is unevenly narrowed by 2-3 times. Maximum narrowing in places of maximum load (usually the inside of the joint). Along the edges of the articular surfaces there are large osteophytes, sclerosis of the endplate, and subchonar bone cysts. Moderate deformation of the bone epiphyses, disruption of the congruence of the articular surfaces.

Clinically - dysfunction of the knee in the form of limited movements, crunching, limping. Often there is slight local swelling and atrophy of the periarticular soft tissues.

Third stage of gonarthrosis

The intraarticular gap is barely noticeable or has disappeared. Many sharp massive osteophytes completely surround the articular surfaces. Gross deformation of the articulating surfaces (expansion and flattening), osteosclerosis of the epiphyses of the bones forming the joint, the presence of cysts. The joint is deviated from the vertical axis.

Clinically - visual deformation of the knee (thickening), forced position, immobility. Atrophy of all muscles of the lower limb, especially the quadriceps. Lameness, movement with the help of crutches, canes, walkers, constant excruciating pain. Patient's disability.

Forms of subchondral osteosclerosis

Taking into account the location and volume of the lesion, the following are distinguished:

• Limited osteosclerosis . In a limited form, the focus of osteosclerosis is presented against the background of healthy tissue within the range of one anatomical formation.
• Extensive osteosclerosis . Extensive sclerosis affects one or more limbs or anatomical areas. The common form is caused by diseases such as Leri's melorheostosis, Paget's disease, as well as malignant neoplasms with metastases.
• Systemic osteosclerosis. Systemic osteosclerosis can be caused by a number of factors. This form of the disease completely affects the skeleton and facet joints that articulate the bones.

Treatment of arthrosis of the knee joint

Treatment of arthrosis of the knee joint is complex, including drug therapy, physiotherapy, surgical interventions, therapeutic exercises, and diet therapy. The range of therapeutic measures depends on the degree of cartilage destruction and clinical manifestations.

Conservative treatment gives a positive result in the first, partly in the second stage of the disease, while most of the cartilage is not yet destroyed.

Drug treatment

Non-steroidal anti-inflammatory drugs (diclofenac, ketoprofen, indomethacin, meloxicam, etc.) are used to relieve pain and inflammation. It is not recommended to take them for a long time, as they negatively affect the synthesis of proteoglycans, which causes dehydration and accelerated cartilage destruction. In addition, they have unwanted side effects from the gastrointestinal tract.

Chondroprotectors (glucosamine and chondroitin sulfate) nourish cartilage tissue, promote regeneration, improve the production of intra-articular fluid, and normalize lubricating properties. Chondroprotectors are ineffective in the third stage of gonarthrosis, when the cartilage is practically destroyed. To obtain a real treatment result, 2-4 courses of treatment are needed (lasting up to one and a half years).

Glucocorticosteroids (diprospan, hydrocortisone, celeston) quickly and effectively relieve pain and inflammation during synovitis, but arthrosis itself is not treated. The first injection of GCS relieves symptoms more effectively than all subsequent ones. They have many side effects and, with frequent use, negatively affect cartilage tissue. Moreover, glucocorticoids are dangerous for diabetes mellitus, arterial hypertension, renal failure, and peptic ulcer disease.

Hyaluronic acid preparations are a modern and safe way to treat arthrosis. Act in the joint as a natural synovial fluid. Sodium hyaluronate covers damaged cartilage with a protective film, preventing further destruction and improves gliding. Penetrates deep into the cartilaginous lining, improving firmness and elasticity, restoring shock-absorbing properties. They start the process of producing their own hyaluronic acid. As a result, the biomechanics of the joint is normalized, pain is relieved, and mobility is restored.

Important!
HA drugs are destroyed in the inflamed joint. Therefore, you first need to stop the symptoms of synovitis with the help of GCS and NSAIDs.

HA preparations:

HYAL-SIN - 1% high molecular weight hyaluronic acid. The course of treatment includes three injections with an interval of 7-10 days.

HYAL-SIN PROLONG - 2% high molecular weight hyaluronic acid. The high concentration of hyaluronic acid makes it possible to reduce the course of treatment to two injections, while simultaneously enhancing the intra-articular effect of the drug and prolonging the effect.

GYAL-SYN PROLONG PLUS -2% long-acting high molecular weight HA (12-24 months) for single use. Intermolecular cross-linking of the HA chains of this drug is carried out for a longer effect and resistance to destruction. One injection per course of treatment. Applicable only to the knee joint.

The most effective is an integrated approach: when all methods of conservative therapy are used.

Surgery

For advanced forms of KLA, the method of choice is knee replacement. This is the replacement of the knee joint with a functional endoprosthesis. Implants made of high-tech alloys (titanium, cobol-chromium, etc.) are strong, rigid, elastic, and biocompatible with human tissue.

Endoscopic arthroscopy with minimally invasive manipulations is performed if the course of the disease is complicated by ruptures of the ligaments, meniscus, or the entry of a bone fragment into the joint capsule.

Physiotherapy

Complex treatment of stages 1-2 of OAC includes shock wave therapy, ultrasound, manual techniques, iontophoresis, mechanical traction of the joint, laser therapy, thermal treatment, cryotherapy (local cooling). A good effect is obtained by combining manual therapy with traction.

Diet therapy

Age-related osteoarthritis is associated with the loss of calcium salts, which provokes microcracks in bones and fragility of osteophytes. Patients with OAC are advised to follow a non-strict diet, which includes:

• consumption of lean meat, fish, seafood;
• introduction of high-protein ingredients (nuts, legumes, wheat germ) into the diet;
• dishes that include plant and animal collagen (jelly, aspic, jellied meat);
• dairy products;
• ban on fatty, salty, spicy foods.

People who are overweight are prescribed a more strict diet to lose weight.

Physiotherapy

Therapeutic gymnastics strengthens muscles and activates blood circulation in the joint. Use exercises without maximum flexion and extension. Instead of the usual dynamic exercises, static ones are used. For example, lying on your back, raise your outstretched leg and keep it suspended for some time.

Important!
To strengthen muscles and ligaments, do static or slow dynamic exercises. If the exercise causes sharp pain, then it is contraindicated or performed incorrectly.

How to treat pathology

Complex treatment methods are used to restore mobility, tissue blood flow, and eliminate discomfort.

The following types of medications are used:

• non-steroidal anti-inflammatory drugs based on diclofenac;
• systemic painkillers (Nise, Ketorol);
• antihistamines to eliminate swelling and inflammation (Zodak, Suprastin);
• antibiotics;
• hormonal drugs in the absence of effect from NSAIDs (based on dexamethasone, hydrocortisone);
• chondroprotectors.

If stage 1-2 is observed, oral medications are prescribed. In the presence of severe deviations, injections are required so that the drug completely passes into the bloodstream, bypassing physiological barriers.

If motor function is absent, surgery is prescribed. It is performed under general anesthesia, eliminating excess bone formations and normalizing local blood flow.

Forecast. Prevention

Osteoarthritis of the knee joint is difficult to treat and is one of the ten main causes of disability in the Russian Federation and Belarus. However, in the early stages, the progression of the disease can be significantly slowed down. If there are risk factors for the purpose of prevention, it is recommended to:

• balanced loads on joints (optimal training and work regimen);
• swimming;
• massage of thigh and calf muscles;
• maintain optimal weight;
• rejection of bad habits;
• regular physical therapy exercises;
• wear comfortable shoes, do not get too cold, do not overwork;
• diet therapy;
• treatment of concomitant diseases.

Long-acting hyaluronic acid preparations GIAL-SIN, GIAL-SIN PROLONG, GIAL-SIN PROLONG PLUS will improve trophism and slow down the degeneration of the cartilage lining of the knee. Course treatment is the key to achieving a positive effect. The duration of therapeutic and preventive action is 12-24 months.

What physiotherapeutic methods are most often used in stages 1 and 2

• Electrophoresis with medications.
• Paraffin therapy to stimulate blood flow.
• Laser therapy to stop the growth of osteophytes and destroy existing ones.
• Mud compresses to eliminate atrophic changes in tissues.
• Acupuncture to reduce pain and restore muscle tone.
• Massage is relevant at the rehabilitation stage.
• Physiotherapy.

With the help of simple gymnastics, you can eliminate pain in the initial stages of arthrosis of the elbow joint. Contraindications to it are recent elbow injuries, elevated body temperature, influenza, ARVI, as well as a period of 3 months after surgery on the elbow joint.